I had only CF guitars until a week ago when I received an LX1 from MF (my wife is starting to book more travel and even getting a small CF guitar on an airplane is a hassle -- the LX1 is disposable in comparison). It has sat in my basement (dehumidified to 50% RH) for the last week and the top appears absolutely flat. Does Martin make that model with no top radius?

BTW, it is impressive for what it can do for its size and I presume the medium strings give it the big edge over the Baby Taylor volume and tone wise.

Whether it is built in or not, the string pull should induce a slight doming of the top.

Since I bought this guitar as something that I don't care if it is cracked or abused by an airline, this is really just an academic question. There is a slight bulge behind the bridge but it looks like it was manufactured with no radius. The Martin Guitar Forum has some posts saying a top radius of about 50 feet is the Martin standard (does not make it true...).

Another interesting tidbit, the bridge plate is a triangle (goes all the way into the X-corner) of the same mahogany photo HPL as the back and sides. The bridge pin drilling looks perfect on the inside. At its price point I can't imagine they take the trouble to put something in the guitar while drilling. Maybe this is another aspect of HPL. When drilled from the "glue" side there is no splintering.

They do radius the top all be it a very shallow one. It's one of the reasons you get that bass boomyness imho. But like Roger said typically you are going to have some string pull bellying anyway. Unless it's really over braced perhaps.